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1.
This paper presents a study on the resource and environmental profile of leather for communicating to the consumers about the environmental burdens of leather products. The results indicate that significant environmental impacts were caused during the tanning and finishing of leather as well as the electricity production and transportation required in the life cycle. The use of fossil fuels in the production of energy has greater impact with increased emissions leading to about 15190 kg CO2 equivalent of global warming and about 73 kg SO2 equivalent of acidification while producing 100 m2 of leather for shoe uppers. Further resource use of 174 kg of coal, 6.5 kg of fuel oil, 17.4 m3 of water and 348 kg of chemicals of which about 204 kg are hazardous are consumed, and wastewater of about 17 m3, BOD of 55 kg, COD of about 146 kg, TDS of 732 kg and solid waste of about 1445 kg are generated during the life cycle for the production of 100 m2 of leather. The total solid waste generated is 1317 kg, out of which about 80% is biodegradable contributed by slaughtering, tanning and finishing stage, 14% is non-biodegradable contributed by tanning, finishing and electricity production stages and 6% is hazardous mainly from tanning and finishing stage of leather.  相似文献   

2.
In recent years, the increasing world population and rapid industrial development has increased the consumption of fossil fuel-derived oils. In response to the resulting exhaustion of fossil fuel energy, many countries around the world are investigating methods of waste energy recovery and reuse, including oil recovery from the pyrolysis process of waste tires. This study investigates the efficiency of an ultrasound-assisted oxidative desulfurization (UAOD) process in sulfur reduction from diesel oil and the pyrolysis oil from waste tires treatment. The results indicate that the oxidation efficiency increases as the doses of transition metal catalyst are increased. Longer sonication time also enhances the oxidation process, apparently through the biphasic transfer of oxidants, which results in a high yield of organic sulfur oxidation products. The best desulfurization efficiency was 99.7% (2.67 ppm sulfur remaining) and 89% (800 ppm sulfur remaining) for diesel and pyrolysis oils, respectively, via a process executed by two UAOD units connected in series and combined with solid adsorption using 30 g of Al2O3 in 6 cm columns. These batch experiment results demonstrate clean waste energy recovery and utilization, while fulfilling the requirements of Taiwan EPA environmental regulations (sulfur concentrations less than 5000 ppm).  相似文献   

3.
This study proposes a new approach for diosgenin production from Dioscorea zingiberensis C. H. Wright tubers with respect to resources utilization and clean production. This process consisted of two successive parts, i.e., recovery of starch from raw material, and microbial hydrolysis of the residue to produce diosgenin by Trichoderma reesei. In the first step, about 75.4% of hemicellulose and 98.0% of starch were removed from the tubers. In the second step, about 90.2% of diosgenin was released from saponins by T. reesei at 30 °C, at an aeration of 0.80 vvm and agitation rate of 300 rpm in a 5.0 L bioreactor. Significant reduction of pollutant production was detected by replacing the traditional approach with the proposed new method. About 99.2% of reducing sugar, 99.4% of chemical oxygen demand, 99.2% of total organic carbon, 100% of SO42?, and 100% of acid was reduced in the new processing wastewater.  相似文献   

4.
Using the organic fraction of municipal solid waste (OFMSW) for biogas production might contribute to greenhouse gas mitigation, but emissions linked with biogas production can reduce these beneficial effects. Therefore the emissions of NH3, CH4 and N2O and costs caused by treating OFMSW by co-fermentation with slurry were calculated in detail from literature data, and strategies for reducing emissions were evaluated. Emission factors were calculated for single gases during storage and after application. The sensitivity of the calculations concerning the organic dry matter content of OFMSW, retention time and CH4-yield was analyzed. The anaerobic co-fermentation of OFMSW increased biogas yields and contributed to the reduction of CO2 emissions with 32 to 152 kg CO2 t−1 organic waste depending on application and storage techniques used for the fermentation residues. Considering a payment of 0.1 €/kWh for the electricity produced, the costs for utilization of OFMSW in slurry based biogas plants were calculated to range between 34 and 38  t−1. Measures for mitigating greenhouse gas emissions by covering the fermentation residue stores proved to be more cost effective with 3–31  t−1 CO2 compared to immediate harrowing or injecting the residues during field application.  相似文献   

5.
Process of obtaining CaCO3 from the waste post-distillation liquid DS and post-filtration liquid from Solvay method of the soda production at 303 K was investigated. Reagents were dosed in a stoichiometric ratio without dilution, for different concentrations of the DS and post-filtration liquids. The dosage time was varied in the range 2–30 min, the reagent stirring rate was 500 rpm. For the obtained samples of CaCO3, the bulk and packing densities, water, paraffin oil and dibutyl phthalate absorption capacities, distribution of the particle size as well as the crystalline form were determined.  相似文献   

6.
Close relationships among climatic factors and soil respiration (Rs) are commonly reported. However, variation in Rs across the landscape is compounded by site-specific differences that impede the development of spatially explicit models. Among factors that influence Rs, the effect of ecosystem age is poorly documented. We hypothesized that Rs increases with grassland age and tested this hypothesis in a chronosequence of tallgrass prairie reconstructions in central Iowa, U.S.A. We also assessed changes in root biomass, root ingrowth, aboveground net primary productivity (ANPP), and the strength of soil temperature and moisture in predicting Rs. We found a significant increase in total growing season Rs with prairie age (R2 = 0.79), ranging from 714 g C m?2 in the youngest reconstruction (age 4) to 939 g C m?2 in the oldest prairie (age 12). Soil temperature was a strong predictor of intra-seasonal Rs among prairies (R2 = 0.78–0.87) but mean growing season soil temperature and moisture did not relate to total Rs. The increase in Rs with age was positively correlated with root biomass (r = 0.80) and ANPP (r = 0.87) but not with root ingrowth. Our findings suggest that growing season Rs increases with tallgrass prairie age, root biomass, and ANPP during young grassland development.  相似文献   

7.
Kinetics of enzymatic unhairing by protease in leather industry   总被引:2,自引:0,他引:2  
In leather industry, unhairing is a heavy pollution operation. The conventional lime-sulfide process produces a large amount of sulfide which is toxic to health and difficult to dispose. Moreover, conventional lime-sulfide process leads to the destruction of the hair causing increased COD, BOD and TDS loads in the effluent. As an alternative method, enzymatic unhairing is a promising clean technology. The main utilized enzyme preparations are proteases.There are many reports about enzymatic unhairing, most of which are qualitative. The kinetics of enzymatic unhairing by protease was discussed in this article. It will provide useful information to enzymatic unhairing. In our research, by analysis of the concentrations of released total protein in enzyme bath during protease unhairing, the good linearity between released total protein and square root of time (min1/2) was obtained at the initial stage. The good linearity suggests that enzymatic unhairing by protease is a diffusion-controlled process at the initial stage. The analysis of kinetics of released saccharides also confirms the same conclusion. On the other hand, the same characteristics between the kinetics of released saccharides and that of released total protein further confirms that it is the hydrolysis of core protein by protease that leads to the degradation of proteoglycans and the release of protein and saccharides. However, in our tests, the kinetics of released collagen indicates that the injury to skin took place in 3-6 h. Therefore, it’s necessary to control the time of protease unhairing within an appropriate limit.  相似文献   

8.
Nitrous oxide (N2O) and ammonia (NH3) emissions from surface applied high (HN) and low (LN) nitrogen pig manures were measured under field conditions. Manures were band-spread to a winter wheat crop at three growth stages—mid-tillering, stem elongation and flag leaf emergence. The N2O flux rates were measured using the static chamber technique while NH3 volatilisation was assessed using a micrometeorological mass balance technique with passive flux samplers. The N2O emissions were episodic in nature with flux rates observed ranging from 2.8 to 31.5 g N2O–N ha?1 day?1 (P < 0.001). Higher N2O emissions generally occurred after rainfall events. Highest N2O losses were observed from the HN treatment with LN manure use decreasing emissions by 18% (P < 0.03). The NH3 volatilisation rates were highest within 1 h of manure application with 95% of emissions occurring within 24 h (P < 0.001). Cumulative N loss was highest at mid-tillering as low crop canopy cover and increased wind-speeds enhanced NH3 loss (P < 0.001). Highest emissions were measured from the HN manure (P < 0.03). Total ammoniacal N loss ranged from 6 to 11%. Crop N uptake and grain yield were unaffected by application timing or manure type. Therefore, the use of LN manures decreased gaseous emissions of N2O and NH3 without any adverse effects on crop performance.  相似文献   

9.
Slurries are a significant source of CH4, NH3 and N2O emissions to the atmosphere. The research project aimed at quantifying CH4, NH3 and N2O emissions from liquid manure stores and after manure application under field conditions. The influence of the manure treatment options “no treatment”, “slurry separation”, “anaerobic digestion”, “slurry aeration” and “straw cover” on the emission level was investigated. Approximately 10 m3 of differently treated slurry were stored in pilot scale slurry tanks. Emissions were followed for c. 80 days. After the storage period, slurries were applied to permanent grassland. Greenhouse gas emissions from slurry were mainly caused by methane emissions during storage and by nitrous oxide emissions after field application of manures. Mitigation of GHG emissions can be achieved by a reduction in slurry dry matter and easily degradable organic matter content. Ammonia emissions mainly occurred after field application. Untreated slurry emitted 226.8 g NH3 m−3 and 92.4 kg CO2 eq. m−3 (storage and field application). Slurry separation (liquid fraction and composting of the solid fraction) resulted in NH3 losses of 402.9 g m−3 and GHG losses of 58.5 kg CO2 eq. m−3. Anaerobic digestion was a very effective means to reduce GHG emissions. 37.9 kg CO2 eq. m−3 were lost. NH3 emissions were similar to those from untreated slurry. Covering the slurry store with a layer of chopped straw instead of a wooden cover increased NH3 emissions to 320.4 g m−3 and GHG emissions to 119.7 kg CO2 eq. m−3. Slurry aeration nearly doubled NH3 emissions compared to untreated slurry. GHG emissions were reduced to 53.3 kg CO2 eq. m−3.  相似文献   

10.
Tillage practices affect the fate of fertilizer nitrogen (N) through influencing transformations of N, but few studies have examined N2O and NH3 emissions, and N leaching from different rice tillage systems. Thus the objective of this study was to assess N2O emission, NH3 volatilization and N leaching from direct seeded rice in conventional tillage (CT) and no-tillage (NT) production systems in the subtropical region of China during the 2008 and 2009 rice growing seasons. Treatments were established following a split-plot design of a randomized complete block with tillage practices as the main plot and N fertilizer level as the sub-plot treatment, and there were four treatments: NT + no fertilizer (NT0), CT + no fertilizer (CT0), NT + compound fertilizer (NTC) and CT + compound fertilizer (CTC), respectively. Results showed that N fertilization significantly increased (p < 0.01) N2O emissions, NH3 volatilization and N leaching from rice fields in both years. In general, there was no significant difference in N2O emissions and NH3 volatilization between NT0 and CT0 in both years, while NTC had significantly higher (p < 0.05) N2O emissions and NH3 volatilization compared to CTC. Over the two rice growing seasons, NTC showed 32% and 47% higher N2O emissions, and 29% and 52% higher NH3 losses than CTC. Higher (p < 0.05) N2O emissions from NTC than CTC were presumably due to higher soil organic C and greater denitrification. Total N and NO3? concentrations were higher (p < 0.05) in CTC than NTC, but larger volumes of percolation water in NTC than CTC resulted in no significant difference in leakage of total N and NO3?. Hence, application of N fertilizer in combination with NT appeared to be ineffective in reducing N losses from N fertilizer in paddy fields.  相似文献   

11.
In the United Kingdom, as with other European countries, land-based emissions of NOx and SO2 have fallen significantly over the last few decades. SO2 emissions fell from a peak of 3185 Gg S in 1970 to 344 Gg S in 2005 and are forecast by business-as-usual emissions scenarios to fall to 172 Gg by 2020. NOx emissions were at a maximum of 951 Gg N in 1970 and fell to 378 by 2005 with a further decrease to 243 Gg N forecast by 2020. These large changes in emissions have not been matched by emissions changes for NH3 which decreased from 315 Gg N in 1990 to 259 in 2005 and are forecast to fall to 222 by 2020. The Fine Resolution Atmospheric Multi-pollutant Exchange model (FRAME) has been applied to model the spatial distribution of sulphur and nitrogen deposition over the United Kingdom during a 15-year time period (1990–2005) and compared with measured deposition of sulphate, nitrate and ammonium from the national monitoring network. Wet deposition of nitrogen and sulphur was found to decrease more slowly than the emissions reductions rate. This is attributed to a number of factors including increases in emissions from international shipping and changing rates of atmospheric oxidation. The modelled time series was extended to a 50-year period from 1970 to 2020. The modelled deposition of SOx, NOy and NHx to the UK was found to fall by 87%, 52% and 25% during this period. The percentage area of sensitive habitats in the United Kingdom for which critical loads are exceeded is estimated to fall from 85% in 1970 to 37% in 2020 for acidic deposition and from 73% to 49% for nutrient nitrogen deposition. The significant reduction in land emissions of SO2 and NOx focuses further attention in controlling emissions from international shipping. Future policies to control emissions of ammonia from agriculture will be required to effect further significant reductions in nitrogen deposition.  相似文献   

12.
Increasing use of poly crystalline diamond (PCD) inserts as cutting tools and wear parts is vividly seen in automobile, aerospace, marine and precision engineering applications. The PCD inserts undergo series of manufacturing processes such as: grinding that forms the required shape and polishing that gives a fine finish. These operations are not straight forward as PCD is extremely resistant to grinding and polishing. Single crystal diamond can easily be polished by choosing a direction of easy abrasion, but polishing a PCD imposes serious difficulties as the grains are randomly oriented. Prior research on polishing of PCD inserts includes electro discharge grinding (EDG), dynamic friction polishing and grinding by a vitrified bonded diamond wheel. The surface textures of PCD produced using an EDG process often contains: micro cavities, particle pullout, micro-grooves, chipped edges, cracks and gouch marks. While applying the dynamic friction polishing method the PCD material undergoes phase transformation and hence increased polishing rate was apparently seen. However the phase transformation of PCD deteriorates the strength of the insert. Furthermore the inserts produced using the dynamic polishing method often exhibits cracks, chip off and edge damage while using as a cutting tool. Therefore, a new method “aero-lap polishing” was attempted as it applies controlled amount of impinging force by which the surface damage can be significantly reduced. The study did establish an improvement of surface finish of PCD from Ra = 0.55 μm, Rt = 4.5 μm to Ra = 0.29 μm, Rt = 1.6 μm within 15–25 min of polishing time along with significant reduction in surface defects.  相似文献   

13.
For the removal of phosphate (PO43 -) from water, an adsorbent was prepared via carbonization of sewage sludge from a wastewater treatment plant: carbonized sludge adsorbent (CSA). The mechanism of phosphate removal was determined after studying the structure and chemical properties of the CSA and its influence on phosphate removal. The results demonstrate that phosphate adsorption by the CSA can be fitted with the pseudo second-order kinetics and Langmuir isotherm models, indicating that the adsorption is single molecular layer adsorption dominated by chemical reaction. The active sites binding phosphate on the surface are composed of mineral particles containing Si/Ca/Al/Fe. The mineral containing Ca, calcite, is the main factor responsible for phosphate removal. The phosphate removal mechanism is a complex process including crystallization via the interaction between Ca2 + and PO43 -; formation of precipitates of Ca2 +, Al3 +, and PO43 -; and adsorption of PO43 - on some recalcitrant oxides composed of Si/Al/Fe.  相似文献   

14.
Diosgenin (CAS number 512-04-9) production from Dioscorea zingiberensis is a very important industry in central-western China. However, treatment of the wastewater with COD up to 50,000 mg/L has been a formidable challenge for the sustainable development of diosgenin industry. A cleaner production process, called the saccharification–membrane retrieval–hydrolysis (SMRH) process, was proposed and pilot-tested by us. The new process combines traditional acid hydrolysis with enzyme hydrolysis and UF/NF technologies. It has two major advantages. (1) The starch in D. zingiberensis is degraded into low molecular weight soluble sugar which is separated and removed before acid hydrolysis of the residue. This prevents the soluble sugar from entering the wastewater; instead it can be utilized as a carbon source in the fermentation industries. (2) UF/NF membrane equipment separates the acid hydrolysis solution into three parts: (a) the colloid phase, (b) the acid solution and (c) the water. All of which can be used in this or in another industry. In this way, the new production process dramatically reduces the wastewater discharge and uses the sugar, acid, water and solid waste in other processes.  相似文献   

15.
This paper combines life-cycle analyses and economic analyses for Miscanthus and willow heat and electricity fuel-chains in Ireland. Displaced agricultural land-uses and conventional fuels were considered in fuel-chain permutations. Avoided greenhouse gas (GHG) emissions ranged from 7.7 to 35.2 t CO2 eq. ha−1 a−1. Most fuel-chain permutations exhibited positive discounted financial returns, despite losses for particular entities at a farm-gate processed-biomass price of €100 t−1 dry-matter. Attributing a value of €10 t−1 CO2 eq. to avoided GHG emissions, but subtracting financial returns associated with displaced fuel supplies, resulted in discounted annual national economic benefits (DANEBs) ranging from −457 to 1887€ ha−1 a−1. Extrapolating a plausible combination of fuel-chains up to a national indicative scenario resulted in GHG emission avoidance of 3.56 Mt CO2 eq. a−1 (5.2% of national emissions), a DANEB of 167 M€, and required 4.6% of national agricultural land area. As cost-effective national GHG avoidance options, Miscanthus and willow fuel-chains are robust to variation in yields and CO2 price, and appear to represent an efficient land-use option (e.g. compared with liquid biofuel production). Policies promoting utilisation of these energy-crops could avoid unnecessary, and environmentally questionable, future purchase of carbon credits, as currently required for national Kyoto compliance.  相似文献   

16.
Biodiesel, produced from various vegetable and/or animal oils, is one of the most promising alternative fuels for transportation in Thailand. Currently, the waste oils after use in cooking are not disposed adequately. Such oils could serve as a feedstock for biodiesel which would also address the waste disposal issue. This study compares the life cycle greenhouse gas (GHG) emissions from used cooking oil methyl ester (UCOME) and conventional diesel used in transport. The functional unit (FU) is 100 km transportation by light duty diesel vehicle (LDDV) under identical driving conditions. Life cycle GHG emissions from conventional diesel are about 32.57 kg CO2-eq/FU whereas those from UCOME are 2.35 kg CO2-eq/FU. The GHG emissions from the life cycle of UCOME are 93% less than those of conventional diesel production and use. Hence, a fuel switch from conventional diesel to UCOME will contribute greatly to a reduction in global warming potential. This will also support the Thai Government's policy to promote the use of indigenous and renewable sources for transportation fuels.  相似文献   

17.
Dietary adjustments have been suggested as a means to reduce N losses from dairy systems. Differences in fertilizing value of dairy slurry as a result of dietary adjustments were evaluated in a 1-year grassland experiment and by long-term modelling. Slurry composition of non-lactating dairy cows was manipulated by feeding diets with extreme high and low levels of dietary protein and energy. C:Ntotal ratio of the produced slurries ranged from 5.1 to 11.4. To evaluate their short-term fertilizer N value, the experimental slurries (n = 8) and slurries from commercial farms with variable composition (n = 4), were slit-injected in two grassland fields on the same sandy soil series in the north of The Netherlands (53°10′N, 6°04′E), with differences in sward age and ground water level. The recently established grassland field (NEW) was characterized by lower soil OM, N and moisture contents, less herbs and more modern grass varieties compared to the older grassland field (OLD). Slurry was applied in spring (100 kg N ha−1) and after the first cut (80 kg N ha−1) while in total four cuts were harvested. Artificial fertilizer N treatments were included in the experiment to calculate the mineral fertilizer equivalent (MFE) of slurry N. The OLD field showed a higher total N uptake whereas DM yields were similar for the two fields. Average MFE of the slurries on the OLD field (47%) was lower than on the NEW field (56%), probably as a result of denitrification of slurry N during wet conditions in spring. Slurries from high crude protein diets showed a significantly higher MFE (P < 0.05) compared to low crude protein diets. No significant differences in MFE were observed between slurries from high and low energy diets. On both fields, MFE appeared to be positively related to the ammonium content (P < 0.001) and negatively to the C:Ntotal ratio of the slurry DM (P = 0.001). Simulation of the effect of long-term annual application of 180 kg N ha−1 with highest and lowest C:Ntotal ratio suggested that both slurries would lead to an increase in annual soil N mineralization. Both soil N mineralization and SOC appeared to be substantially higher in equilibrium state for the slurry with the highest C:Ntotal ratio. It is concluded that in a situation with slit-injection, the reduced first-year N availability of slurry with a high C:Ntotal ratio as observed in the grassland experiment will only be compensated for by soil N mineralization on the very long term.  相似文献   

18.
One-year winter wheat–summer maize rotation is the most popular double cropping system in north-central China, and this highly productive system is an important source of nitrous oxide (N2O) and nitric oxide (NO) emissions due to the high fertilizer N and irrigation water inputs. To sustain the high crop production and mitigate the detrimental impacts of N2O and NO emissions, improved management practices are extensively applied. The aim of this study is therefore to evaluate the effects of an improved management practice of irrigation, fertilization and crop straw on grain yield and N2O and NO emissions for a wheat–maize rotation field in northern China. Using automated and manual chamber measuring systems, we monitored N2O and NO fluxes for the conventional (CT, 2007–2008), improved (IT, 2007–2008), straw-amended (WS, 2008–2009), straw-not-amended (NS, 2008–2009), and no N-fertilizer treatments (WS–NN, 2008–2009), respectively, for one rotation-year. The grain yields were determined for CT and IT for three rotation-years (2005–2008) and for WS, NS and WS–NN for one rotation-year (2008–2009). The improved management of irrigation and fertilization reduced the annual N fertilization rate and irrigation amount by 17% and 30%, respectively; increased the maize yield by 7–14%; and significantly decreased the N2O and NO emissions by 7% (p < 0.05) and 29% (p < 0.01), respectively. The incorporation of wheat straw increased the cumulative N2O and NO emissions in the following maize season by 58% (p < 0.01) and 13%, respectively, whereas the effects of maize straw application were not remarkable. The N2O and NO emission factors of applied N were 2.32 ± 2.32% and 0.42 ± 1.69% for wheat straw and 0.67 ± 0.23% and 0.54 ± 0.15% for chemical N-fertilizers, respectively. Compared to conventional management practices using high application rates of irrigation water and chemical N-fertilizer as well as the field burning of crop straw, the improved management strategy presented here has obvious environmentally positive effects on grain yield and mitigation of N2O and NO emissions.  相似文献   

19.
The projected increase of atmospheric CO2 concentration [CO2] is expected to increase yield of agricultural C3 crops, but little is known about effects of [CO2] on lodging that can reduce yield. This study examined the interaction between [CO2] and nitrogen (N) fertilization on the lodging of rice (Oryza sativa L.) using free-air CO2 enrichment (FACE) systems installed in paddy fields at Shizukuishi, Iwate, Japan (39°38′N, 140°57′E). Rice plants were grown under two levels of [CO2] (ambient = 365 μmol mol−1; elevated [CO2] = 548 μmol mol−1) and three N fertilization regimes: a single initial basal application of controlled-release urea (8 g N m−2, CRN), split fertilization with a standard amount of ammonium sulfate (9 g N m−2, MN), and ample N (15 g N m−2, HN). Lodging score (six ranks at 18° intervals, with larger scores indicating greater bending), yield, and yield components were measured at maturity. The lodging score was significantly higher under HN than under CRN and MN, but lodging was alleviated by elevated [CO2] under HN. This alleviation was associated with the shortened and thickened lower internodes, but was not associated with a change in the plant's mass moment around the culm base. A positively significant correlation between lodging score and ripening percentage indicated that ripening percentage decreased by 4.5% per one-unit increase in lodging score. These findings will be useful to develop functional algorithm that can be incorporated into mechanistic crop models to predict rice production more accurately in a changing climate and with different cultural practices.  相似文献   

20.
Rice (Oryza sativa L.) paddies are one of the major sources of atmospheric methane (CH4), a greenhouse gas. To elucidate the quantitative relationship between CH4 emission from rice paddies and temperature, 6 years data of CH4 emission from pot experiments were analyzed in terms of the sum of effective temperature (∑(T−15); T is the daily mean air temperature (°C)). The base temperature of 15 °C was adopted as the 0 °C physiological temperature for methanogens. Significant positive correlations between total CH4 emission throughout the rice growth period and ∑(T−15) were observed for pots with rice straw (RS) application at a rate of 6 g kg−1 soil, which corresponds to 6 t ha−1 (r=0.83071), and those without RS application (r=0.81871). It was confirmed that temperature is a major factor affecting the interannual variation in CH4 emission. For the 1993 and 1995 data sets that include seven and four levels of RS application, the relationship between seasonal CH4 emission and RS application rate could be expressed using linear functions (r=0.98871, 0.99671), the slopes of which were similar to each other. Based on these findings, we confirmed that the dependence of seasonal CH4 emission on both temperature and RS application rate can be described by a single linear equation.  相似文献   

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